Spirit-level



(No Model'J v O. P. RICHARDSON.

' SPIRIT LEVEL-I No. 570,056., Patented 001;. 27, 1896.

UNITED STATES PATENT OFFICE.

CHARLES F. RICHARDSON, OF ATHOL, MASSACHUSETTS.

SPIRIT-LEVEL.

SPECIFICATION forming part of Letters Patent No. 570,056, dated October 27, 1896.

Application filed February 1, 1896- Serial No. 577,768 (No model.)

- To all whom it may concern.-

Be it known that I, CHARLES F. RICHARD- SON, a citizen of the United States, residing at Athol, in the county of WVorcester and State of Massachusetts, have invented a new and useful Improvement in Spirit-Levels, of which the following is a specification, reference being had to the accompanying drawings, forming a part of the same, in which Figure 1 represents a side view of a spiritlevel embodying my improvement. Fig. 2 is a side view of one end ofmy improved level. Fig. 3 is an end view; and Fig. 4 represents a portion of the level shown in sectional view on line 4 4, Fig. 3.

Similar letters refer to similar parts in the different figures.

The object of my present invention is to provide means for varying the position of one end of the level with reference to its supporting-surface, whereby the inclination of the surface upon which the level is supported may be determined; and it consists in providing one end of the level with a sliding plate oapable of being moved below the bottom surface of the level and in means for actuating the same, whereby it is moved and locked in position by the same device.

A denotes the frame of a spirit-level embodying my improvement. I

B is a sliding plate provided with slots B B, through which screws B B having heads B pass and enter the end of the frame A, allowin g the plate B to slide freely on the screws B The frame A is provided with an opening A and also with a slot A between the opening A and the end of the frame to receive an arm C, which is held in the plate B and extends into the opening A and having its innor end flattened as at C and enterin an annular groove D-in the circular nut D,which is carried upon a screw E, held in a fixed position in the frame A. By raising the nut D on the screw E in the position shown in Fig. 4 the arm C is moved to the upper end of the slot A and the plate B is made to coincide with the end of the frame A, allowing the level to be used in the ordinary manner. moving the nut D downward upon the screw E the sliding plate B is moved downward, bringing its lower end B below the bottom surface of the frame A and forming a support for the end of thelevel, as represented in Fig. 1, thereby raising that end of the level to correspond with the inclination of the surface F upon which the level is supported. The edge of the sliding plate B is graduated at B and the frame A of the level is provided with an indicator-mark A in order to indicate the amount of inclination of the supporting-surface F in the length of the frame A.

I am aware that a sliding plate attached to the end of a spirit-level for. the purpose of providing a support by which the end of the level is raised is not new, and I do not claim such broadly. By means of my present invention I am able to adjust the position of the sliding plate by means of a screw-feed,

which not only enables the plate to be moved through very minute distances, but also holds it against displacement without the use of other tightening or looking devices.

hat I claim as my invention, and desire to secure by Letters Patent, is-

The combination with the frame of a spirit level, provided with an opening A near its end and a slot A between said opening and the end, of a sliding plate capable of sliding vertically upon the end of the level, an arm C projecting from said sliding plate through said slot into said opening, a fixed screw held in the frame of the level parallel with said sliding plate and passing through said opening and a grooved nut held in said screw and engaging said arm, substantially as described.

Dated the 28th day of January, 1896.

CHARLES F. RICHARDSON. lVitnesses:

MINERVA R. PITTS, ANDREW J. HAMILTON. 

